Ok team, let's have a look...
SG500, SP1k, SG1k, SP1.5k. Mild steel clad Shirogami 2 Kiridashi for scratch patterns / polish, and an Aogami 2 blade for sharpening. I did try sharpening cheap stainless too, and my impressions of the stones was pretty much the same.
I'm sure I don't need to explain to anyone here what an SG500 polish looks like - you've all got one. And if you don't then you want to take a long, hard look at yourself in the mirror, and ask if you are really, truly
happy with your life choices so far.
The SP1k is considerably finer, this isn't an 'either or' situation, it's probably up at around 800 level imo. Both are relatively consistent in terms of not having different grit scratches within the same stone. There's more contrast in the SP.
The SG1k surprised me quite a lot (for reasons I'll explain later). This is finer again, much more integrated and blended. Little contrast.
And the SP1.5k, which has more contrast than the above, but a more noticeable scratch pattern. There's something about this that I quite like.
Would I choose any of them as a polishing stone over a nice soaker at the same level? Probably not. I might be tempted by the SP1.5k over some of the competition, and frankly the SG500 is so versatile that it’s a bit of a no-brainer for anything.
Onto the pointier end of stuff though...
As I may have hinted earlier - the SG500 is just an awesome stone. If you look at the rate it abrades compared to the level it finishes, then it probably has the largest range of any synth I've used, with the possible exception of the Medium India. Not desperately easy to deburr on.
The paper towel cut from the SP1K is much cleaner, it finishes a good bit higher than the SG500, and it's just a cleaner edge all round. This stone is seriously, seriously impressive for sharpening.
Now through all of this the thing that surprised me most was the SG1K. Possibly because I hadn't used one in a while, but nevertheless - this stone is fast af.
I wasn't actually clocking much difference in speed, or grit, between the Pro and the Glass, they are both very pacey and probably finish below 1k. The glass was very difficult for me to deburr well on though, that's why this cut is so ragged. Quite why the polishes were so different I've no idea.
And last but not least, I shall also have to revise my opinion on the SP1.5K. Little bit of a soak and this is actually a really nice stone. This edge is the only one of the four where I wouldn't necessarily go to another stone after. It's good to go as is.
So there are my hastily cobbled together thoughts about Shapton mid grits.
I was more than a little bit impressed tbh. Every one of these stones is very good; you wouldn't need all of them, but I'd take any. Colour me a fully paid up Shapton fanboy from hereon in.